Fraunhofer-gesellschaft Zur Foerderung Der Angewandten Forschung E.v.

Voiceage Corporation

Koninklijke Philips Corporation N.V.

Nokia Corporation

Dolby International Ab

Nokia Technologies Oy

Philippe Gournay

Redwan Salami

Bruno Bessette

Markus Multrus

Bernhard Grill

Nikolaus Rettelbach

Max Neuendorf

Jérémie Lecomte

Stefan Bayer

Guillaume Fuchs

Ralf Geiger

Roch Lefebvre

Johannes Hilpert

Harald Popp

Ulrich Kraemer

Jimmy Lapierre

Stefan Geyersberger

Milan Jelinek

Frederik Nagel

Julien Robilliard

Lars Villemoes

Gerald Schuller

Albertus Cornelis Den Brinker

Stephan Wilde

Tommy Vaillancourt

Steven Craig Greer

Bernard Grill

Stefam Geyersberger

Raif Geiger

Ulrich KRÄMER

Albertus C Den Brinker

Jeremie Lecomte

An audio encoder has a first information sink oriented encoding branch such as a spectral domain encoding branch, a second information source or SNR oriented encoding branch such as an LPC-domain encoding branch, and a switch for switching between the first and second encoding branches, the second encoding branch having a converter into a specific domain different from the spectral domain such as an LPC analysis stage generating an excitation signal, and the second encoding branch having a specific domain coding branch such as LPC domain processing branch, and a specific spectral domain coding branch such as LPC spectral domain processing branch, and an additional switch for switching between the specific domain coding branch and the specific spectral domain coding branch. An audio decoder has a first domain decoder, a second domain decoder, and a third domain decoder as well as two cascaded switches for switching between the decoders.

Low bitrate audio encoding/decoding scheme having cascaded switches

Audio decoding device and method with decoding branches for decoding audio signal encoded in a plurality of domains

A device and a method for quantizing a LPC filter in the form of an input vector in a quantization domain, comprises a calculator of a first-stage approximation of the input vector, a subtractor of the first-stage approximation from the input vector to produce a residual vector, a calculator of a weighting function from the first-stage approximation, a warper of the residual vector with the weighting function, and a quantizer of the weighted residual vector to supply a quantized weighted residual vector. A device and a method for inverse quantizing of a LPC filter, comprises means for receiving coded indices representative of a first-stage approximation of a vector representative of the LPC filter in a quantization domain and of a quantized weighted residual version of the vector, a calculator of an inverse weighting function from the first-stage approximation, an inverse quantizer of the quantized weighted residual version of the vector to produce a weighted residual vector, a multiplier of the weighted residual vector by the inverse weighting function to produce a residual vector, and an adder of the first-stage approximation with the residual vector to produce the vector representative of the LPC filter in the quantization domain.

Variable bit rate LPC filter quantizing and inverse quantizing device and method

An audio encoder has a first information sink oriented encoding branch, a second information source or SNR oriented encoding branch, and a switch for switching between the first encoding branch and the second encoding branch, wherein the second encoding branch has a converter into a specific domain different from the spectral domain, and wherein the second encoding branch furthermore has a specific domain coding branch, and a specific spectral domain coding branch, and an additional switch for switching between the specific domain coding branch and the specific spectral domain coding branch. An audio decoder has a first domain decoder, a second domain decoder for decoding a signal, and a third domain decoder and two cascaded switches for switching between the decoders.

An apparatus for processing an audio signal is provided. The apparatus has a signal processor and a configurator. The configurator is adapted to configure the signal processor based on configuration information such that a configurable upsampling factor is equal to a first upsampling value when a first ratio of the second configurable number of samples to a first configurable number of samples has a first ratio value. Moreover, the configurator is adapted to configure the signal processor such that the configurable upsampling factor is equal to a different second upsampling value, when a different second ratio of the second configurable number of samples to the first configurable number of samples has a different second ratio value. The first or the second ratio value is not an integer value.

Apparatus and method for processing an audio signal and for providing a higher temporal granularity for a combined unified speech and audio codec (USAC)

An audio encoder for encoding an audio signal has a first coding branch, the first coding branch comprising a first converter for converting a signal from a time domain into a frequency domain. Furthermore, the audio encoder has a second coding branch comprising a second time/frequency converter. Additionally, a signal analyzer for analyzing the audio signal is provided. The signal analyzer, on the hand, determines whether an audio portion is effective in the encoder output signal as a first encoded signal from the first encoding branch or as a second encoded signal from a second encoding branch. On the other hand, the signal analyzer determines a time/frequency resolution to be applied by the converters when generating the encoded signals. An output interface includes, in addition to the first encoded signal and the second encoded signal, a resolution information identifying the resolution used by the first time/frequency converter and used by the second time/frequency converter.

Multi-resolution switched audio encoding/decoding scheme

An apparatus for encoding includes a first domain converter, a switchable bypass, a second domain converter, a first processor and a second processor to obtain an encoded audio signal having different signal portions represented by coded data in different domains, which have been coded by different coding algorithms. Corresponding decoding stages in the decoder together with a bypass for bypassing a domain converter allow the generation of a decoded audio signal with high quality and low bit rate.

Audio encoding/decoding scheme having a switchable bypass

Growing community of inventors

Sherbrooke, Canada

Philippe Gournay